Search arXiv⌕ Search
Home/Archive/arXiv

arXiv · 0705.1070

Theory of Acoustic Emission for Micro-Cracks Appeared Under the Surface Layer Machining by Compressed Abrasive

A. K. Aringazin·V. D. Krevchik·V. A. Skryabin·M. B. Semenov·G. V. Tarabrin
View original source ↗Read source document ↗Export metadata ↓

Abstract

One of the possible mechanisms for acoustic emission of growing micro-cracks under conditions of the material machining by com-pressed abrasive has been theoretically studied. Physical ground of this mechanism is the dislocation creep in the field of instant contact temperature on stage of micro-cutting with appearance of the wedge-shaped cavity. It has been shown that the energy density for radiated acoustic wave at the moment when the cavity is opened essentially depends on parameters of the material abrasive machining.

Explore related subjects

cond-mat.mtrl-sci

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

A. K. Aringazin, V. D. Krevchik, V. A. Skryabin, M. B. Semenov, G. V. Tarabrin. 2007-05-08. Theory of Acoustic Emission for Micro-Cracks Appeared Under the Surface Layer Machining by Compressed Abrasive. https://arxiv.org/abs/0705.1070

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

arXiv2026

Bond-selective modulation of scalar spin chirality in strained Mn4N

Scalar spin chirality (SSC) underlies a variety of Berry-phase-driven transport phenomena in noncoplanar magnets. Mn4N is a unique ferrimagnetic system in which both collinear and noncoplanar magnetic configurations have been reported at different lattice parameters, featuring vanishing and finite SSC, respectively. However, the microscopic mechanism governing the competition between these magnetic states and the associated modulation of SSC remains unclear. This issue is particularly important for Mn4N because its high magnetic ordering temperature (TN = 740 K) provides an attractive platform for exploring chiral magnetic states and their associated topological functionalities at elevated temperatures. Here, using first-principles calculations, we investigate the strain-driven evolution of the magnetic ground state and SSC in Mn4N and uncover the microscopic origin of the collinear-to-noncoplanar magnetic transition. We demonstrate that tensile strain continuously stabilizes the noncoplanar configuration and enhances SSC, as quantified by the magnitude of the chirality-order vector. Orbital-resolved crystal orbital Hamilton population and charge-density-difference analyses reveal that strain selectively weakens the Mn3c-N hybridization while preserving direct Mn3c-Mn3c interactions, leading simultaneously to the activation of the Mn3c in-plane magnetic moment and the suppression of N-mediated ferromagnetic superexchange between nearest-neighbor Mn3c atoms. This bond-selective electronic response governs the magnetic ground state and consequently controls the emergence and enhancement of SSC in Mn4N. Our work establishes bond selectivity as an effective strategy for engineering SSC in high-temperature ferrimagnetic materials.

cond-mat.mtrl-sci↗
arXiv2026

Ab Initio Spinor Kadanoff-Baym Approach to Nonequilibrium Electron, Phonon and Magnon Dynamics in Itinerant Ferromagnets

This work introduces a theoretical framework based on the Kadanoff-Baym equations in spinor space to study ultrafast magnetization dynamics in itinerant ferromagnetic systems from first principles. By incorporating spin-orbit coupling into the ab initio Hamiltonian and generalizing the self-energies to include terms beyond the charge sector, I derive scattering integrals within the Markov approximation and quasiparticle renormalizations for electrons and phonons in the presence of spin-dependent effective interactions within a many-body perturbation theory approach. I explicitly discuss how magnons emerge in this framework, and derive, through suitable approximations, a closed and tractable set of equations for coupled electron, phonon and magnon dynamics that can be solved from first principles. I discuss the equations of motion within a minimal ferromagnetic model, where the coupled equations are solved numerically. This approach allows one to treat coherent and incoherent magnetic dynamics on an equal footing, paving the way for a first principles understanding of ultrafast magnetic dynamics and demagnetization, and opening to a truly predictive theory of femtomagnetism in periodic systems.

cond-mat.mtrl-sci↗
arXiv2026

On the physical origins of switching diversity in Cu-embedded SiO$_x$ memristive devices

Resistive switching devices with sub-stoichiometric SiO$_x$ and pancake-like Cu nanoparticles (Cu-PCs) exhibit distinct macroscopic current-voltage characteristics classified as capacitive or gradual (interface-type switching) and abrupt or resistive (filamentary-type switching), motivating an analysis of the microscopic processes underlying this diversity. It is proposed that the device defect landscape is largely shaped by two charged defect types, mobile oxygen vacancies and immobile Cu-related defects, whose distributions jointly govern interfacial and bulk transport. An effective one-dimensional cloud-in-a-cell simulation framework is employed to reproduce the phenomenological picture of both interface-type and filamentary-type switching by incorporating the dominant coupled ionic and electronic processes underlying these mechanisms. The model includes oxygen-vacancy drift-diffusion, Schottky-limited injection at the metal/oxide interfaces, and bulk trap-assisted transport via Poole-Frenkel conduction, with Cu-PCs near the top interface treated effectively. A simulation-based parametric study varying voltage stress, sweep rate, and oxide thickness is used to examine how these factors rebalance voltage partitioning and the spatiotemporal electric field distribution, thereby altering vacancy redistribution and the relative contributions of interface- and bulk-limited conduction. Using representative, physically motivated parameter sets informed by prior device-level studies, the simulations accurately reproduce the characteristic $I$-$V$ signatures of seven different experimentally observed switching responses. Overall, the findings help to link microscopic defect landscapes and transport processes to experimentally measured macroscopic responses within a single, self-consistent modeling framework.

cond-mat.mtrl-sci↗